1. Field of the Invention
This invention relates, generally, to circuit breakers and, more particularly, to circuit breakers having adjustable thermal trip means.
2. Description of the Prior Art
The conventional thermal tripping mechanism of a circuit breaker is well known in the art and consists mainly of a movable trip bar which carries a releasable latch. As shown in U.S. Pat. No. 3,211,860, the trip bar is actuated by adjacent bimetal strips which respond to temperature generated by the current flowing through the circuit breaker. A difficulty with some circuit breakers of the type shown in that patent, is the problem of precisely resetting an adjusting screw of one pole to correspond with settings of corresponding screws for the other poles in the circuit breaker so that all screws are engaged by a corresponding bimetal element for the same current rating.